SEL-411L supports data exchange over Ethernet network to provide line current differential (87L) protection for transmission lines with up to 4 terminals. High-speed transmission line differential, distance, and current protection relay provides 1- and 3-pole tripping and reclosing with synchronism check, circuit breaker monitoring, breaker failure protection, and series-compensated line protection logic. Traveling wave fault location option can pinpoint location of fault within tower span.